CN101818379B - Flax fibers and preparation method thereof - Google Patents

Abstract

The invention relates to a flax fiber. The flax fiber has a strength of 3.0-8.0 cN/dtex and a fineness of 1500-3500 branch; preferably, the strength is 4.0-7.0 cN/dtex and the fineness is 1500-3000 branch; moreover Preferably, the strength is 4.5-6.5cN/dtex, and the fineness is 1800-2800 branch; most preferably, the strength is 5.0-6.0cN/dtex, and the fineness is 2300-2700 branch. The invention also relates to the preparation method of the flax fiber, which comprises the steps of pickling, water washing, oxidation, beating, oiling, deoiling water, softening, oiling and humidifying, stacking and mechanical opening. The flax fiber provided by the invention has high strength and fineness, short preparation process and little pollution.

Description

A kind of flax fiber and preparation method thereof

technical field

The invention belongs to the textile field, in particular, the invention relates to a flax fiber and a preparation method thereof. the

Background technique

With the improvement of people's living standards, more and more attention is paid to fashion styles such as moisture absorption, breathability, health care, crispness, and green environmental protection of clothing fabrics, which prompts people to strengthen the reuse and development of natural fiber resources. Flax fiber is an excellent textile raw material. Its fabric has unique styles such as good moisture absorption and heat dissipation, good air permeability, natural texture, soft luster, crisp and generous, which makes it highly preferred by consumers. the

At present, the domestic flax spinning factory mainly adopts the wet spinning method, that is, flax is first beaten into flax (the fineness is coarse, about 200-300 public branches) to produce roving through carding, needle combing, roving and other processes, and then the roving is boiled and bleached. In order to further remove the colloid contained, it is then fed into the spinning frame in a wet state for spinning. The process flow is: combing hemp → humidification and health preservation → blending hemp → sliver forming → long hemp pre-merging (or mixing machine) → drawing frame → long hemp roving → roving boiled and bleached → wet spinning spun yarn → drying → post-processing. This kind of process is complicated, the process is long, and the spinnable count is low. Generally, the yarn fineness is 15-36. It requires high equipment, and the working environment is poor. At the same time, it is wet processing, so it is difficult to process flax and other textiles. The blending of fibers, and the wet spinning is relatively stiff, which is difficult to apply in knitting, and has great limitations in the development of high-grade and multi-variety textile products. the

Patent application 95109371 adopts washing—pickling—scouring—washing—oxygen bleaching—washing to prepare flax roving, which uses sodium dithionite, sodium sulfide, anthraquinone and sodium hydroxide for scouring, and then Then use hydrogen peroxide, and add hydrogen peroxide stabilizer and ED-8 for oxygen bleaching. In the method, scouring and oxygen bleaching are carried out separately, which increases the production links. In addition, a large amount of sodium hydroxide is used in scouring, and the waste water treatment is cumbersome and seriously pollutes the environment; sodium dithionite is highly toxic, causing serious damage to workers during the production process, and the residue of sodium dithionite in the product is harmful to the health of consumers. threaten. the

Patent application 88102614 combines scouring and bleaching into one, and it beats flax into flax, pre-acids it, then boils it, oils it, and finally dries the flax. Potassium hydroxide or sodium hydride is added when it is boiled and bleached. The bleaching agent used is peroxides such as hydrogen peroxide, potassium peroxide or sodium peroxide, and Tween, Siben or triethanolamine oleate is used as a surfactant. In addition, dimethyl sulfone, diethyl sulfone or phenethyl sulfone are added as accelerators. the

Patent application 200610031004 mixes flax and other raw materials with degumming solution in a weight ratio of 1:10-20, degumming at 30-100°C for 1-5 hours, then washing, oiling and drying to obtain fibers for textile use. The degumming agent can be hydrogen peroxide, add sodium phosphate, sodium tripolyphosphate, etc. as a chelating agent, use urea as a hydrogen bond breaker, add water glass or carboxymethyl cellulose as an anti-deposition agent, use sodium sulfite or Sodium bisulfite is a lignin remover. However, the fiber filaments prepared by this method have low fineness and poor fiber strength, so the application in the textile field has great limitations. the

The flax fiber prepared by the above method has low fineness and can only be used for spinning on expensive special equipment. In order to solve the above problems, the flax fiber can be finely treated to further improve the performance of the fiber (especially fineness, softness, etc.), so as to shorten the spinning process, improve production efficiency, improve yarn quality, and broaden the application field. . the

Contents of the invention

One of the purposes of the present invention is to provide a flax fiber. The flax fiber provided by the present invention has higher fineness and strength, and can be spun on other spinning systems. the

The second object of the present invention is to provide a preparation method of the flax fiber. The preparation method provided by the present invention is simple to operate and has little environmental pollution. the

In order to realize the foregoing invention object, the present invention adopts following technical scheme:

A flax fiber, the flax fiber has a strength of 3.0 to 8.0 cN/dtex and a fineness of 1500 to 3500 branch; preferably a strength of 4.0 to 7.0 cN/dtex and a fineness of 1500 to 3000 branch; more preferably the strength 4.5-6.5cN/dtex, fineness 1800-2800 branch; most preferably strength 5.0-6.0cN/dtex, fineness 2300-2700 branch. the

According to the aforementioned flax fiber, it is characterized in that, according to requirements, the length of the fiber after opening can reach 30-80 mm. the

The preparation method of the aforementioned flax fiber comprises the steps of pickling, washing, oxidation, fibrillation, oiling, deoiling water, softening, oiling and humidification, stacking and mechanical opening, and is characterized in that the oxidation The steps are: 8-12kg of water per kilogram of flax fiber, first add sodium carbonate or potassium carbonate, sodium silicate, urea and penetrant JFC to the water, the amount added is 2-6g of sodium carbonate or potassium carbonate, silicon dioxide per liter of water after adding Sodium acid 2 ~ 8g,

2~8g of urea and 1~4g of osmotic agent JFC, add H ₂ O ₂ after complete dissolution, the amount of H ₂ O ₂ is calculated as pure H ₂ O ₂ after adding 3~12g of H ₂ O ₂ per liter of water; preferably per kilogram Flax fiber water 10kg, each liter of water contains 2~4g of sodium carbonate or potassium carbonate, 3~5g of sodium silicate, 3~5g of urea, 2g of penetrant JFC, the amount of H ₂ O ₂ added is calculated as pure H ₂ O ₂ per liter of water after adding Contains H ₂ O ₂ 3~8g.

According to the above-mentioned preparation method, the oxidation step is to put flax in the oxidizing solution, raise the temperature from room temperature to 70-100°C at a constant speed, control the heating time at 20-60 minutes, and the oxidation reaction time is 2.0-4.0 hours; preferably The temperature is raised from room temperature to 70-90°C at a constant speed, the heating time is controlled at 30-40 minutes, and the oxidation reaction time is 1.0-3.0 hours. the

According to the aforementioned preparation method, the pickling step is that the acid concentration is 1 to 3 g/L, the temperature is 35 to 70° C., the bath ratio is 1:8 to 1:12, and the pickling time is 30 to 80 minutes. Preferably, the acid concentration is 1-2g/L, the temperature is 40-50°C, the bath ratio is 1:10, and the pickling time is 40-60min. the

According to the preparation method described above, the oil agent in the described oiling step is mechanical oil, preferably spindle oil or white oil; 10-40g of mechanical oil, 1-8g of NaOH, and 2-10g of detergent are used for every kilogram of flax fiber. , mixed with 8-12kg of water to prepare an emulsion, soak the flax fiber in it, and keep it warm for 0.5-3h in an environment of 60-100°C; preferably use 10-20g of machine oil per kilogram of flax fiber, 3-6g of NaOH, Stir 2-8g of detergent with 10kg of water to make an emulsion, impregnate the flax fiber in it, and keep it warm at 80°C for 1 hour. the

According to the aforementioned preparation method, vegetable oil is used in the oiling and humidifying step, preferably camellia oil or rapeseed oil; vegetable oil, NaOH, detergent and water are stirred to form an emulsion, which is evenly distributed at the output end of the flax machine. The emulsion is sprayed on the flax fiber, and the detergent is a common detergent; per kilogram of flax fiber, vegetable oil 5-40g, NaOH 1-10g, detergent 1-12g, water 50-200g, preferably per kilogram Flax fibers use 10-20g of vegetable oil, 3-6g of NaOH, 2-8g of detergent, and 70-150g of water. the

According to the above-mentioned preparation method, the temperature of the stacking bin is 20-60° C., and the time is 15-60 hours; preferably, the temperature is 25-40° C., and the time is 24-48 hours. the

According to the above-mentioned preparation method, in the mechanical opening step, the gap between the licker-in roller and the cotton feeding plate is 0.10-7.50 mm, preferably 0.12-5.50 mm. the

According to the above-mentioned preparation method, in the mechanical opening step, the cotton feeding plate of the carding machine should be raised by 1-5 cm, preferably 2-3 cm. the

The present invention is described in detail below:

The flax fiber provided by the invention has a strength of 3.0 to 8.0 cN/dtex and a fineness of 1500 to 3500 branch; preferably a strength of 4.0 to 7.0 cN/dtex and a fineness of 1500 to 3000 branch; more preferably a strength of 4.5 to 6.5 cN/dtex, fineness 1800-2800 metric; most preferably strength 5.0-6.0cN/dtex, fineness 2300-2700 metric. the

The flax fiber provided by the invention has high fineness, and can be processed by dry spinning with cotton spinning, wool spinning or ramie spinning equipment which is simpler than traditional flax wet spinning in the prior art, and can be spun pure or blended flax with more than 60 public counts Yarn overcomes the defect that wet flax yarn can only be spun with a coarse count of about 24 to 36, and can be used to make high-grade fabrics, making flax fiber more widely used. the

The present invention prepares the technological process of refined flax fiber as follows:

Flax is beaten into hemp→ pickling→washing→oxidation→fiberizing→oiling→deoiling→softening→oiling and humidification→stacking→mechanical opening. the

The oxidation step is as follows: reacting hydrogen peroxide and lignin to form oxidized lignin that is easily soluble in dilute lye; at the same time, the hydrogen peroxide oxidizes the colloid between the fibers to make the colloid between the fibers bulky and reduce the connection between the fibers Force, so that the fibers can be separated after mechanical action. Preparation of degumming solution and oxidation process: 8-12kg of water per kilogram of flax fiber, that is, the bath ratio is 1:8-1:12. Add additives such as sodium carbonate or potassium carbonate, sodium silicate, urea and penetrant JFC (fatty alcohol polyoxyethylene ether compound) into the water first. The sodium carbonate or potassium carbonate solution is a weak base, and its alkalinity is soft. Appropriate amount of sodium carbonate or potassium carbonate can reduce the damage of alkali to fiber under the condition that the amount of alkali is enough to remove colloid. Sodium silicate is hydrogen peroxide stabilizer, urea has a certain fluffing effect on fiber, and penetrant can increase the effect of chemicals on fiber. Osmosis, the amount added is 2~6g of sodium carbonate, 2~8g of sodium silicate, 2~8g of urea and 1~4g of osmotic agent JFC per liter of water after addition. After completely dissolving, add _{H 2 O 2 .} Calculated by pure H ₂ O ₂ , the content of H ₂ O ₂ per liter of water after addition is 3-12g.

Among them, 10kg of water per kilogram of flax fiber can be further preferred, and each liter of water contains 2-4g of sodium carbonate or potassium carbonate, 3-5g of sodium silicate, 3-5g of urea, 2g of penetrant JFC, and the amount of H ₂ O ₂ added is based on pure H ₂ O ₂ It is calculated as 3~8g of H ₂ O ₂ per liter of water after adding.

In addition, the operation of the oxidation step can be further preferably put flax in the oxidation solution, and the temperature is raised from room temperature to 50-100°C at a constant speed, the heating time is controlled at 20-60 minutes, and the oxidation reaction time is 2.0-4.0 hours; more preferably The temperature is raised from room temperature to 70-90°C at a constant speed, the heating time is controlled at 30-40 minutes, and the oxidation reaction time is 1.0-3.0 hours. the

The pickling effect is to preliminarily remove the pectin on the epidermis of the flax fiber and remove the metal ions in the flax fiber. The metal ion will catalyze the oxidation reaction and cause the hydrogen peroxide to react too quickly, thereby excessively oxidizing the fiber. Too high acid concentration and temperature will cause excessive hydrolysis of cellulose, and too low acid concentration and temperature can not achieve the effect of removing metal ions in pectin and fibers. In the present invention, the pickling process can refer to the prior art pickling However, in order to further improve product quality, the concentration of acid in the preferred pickling process is controlled at 1 to 3g/L, the temperature is at 35 to 70°C, and the bath ratio is 1:8 to 1:12 (that is, 1 kilogram of flax fiber plus 8 to 12 kg of water), the pickling time is 30-80min; more preferably, the acid concentration is 1-2g/L, the temperature is 40-50°C, the bath ratio is 1:10, and the pickling time is 40-60min. the

Described acid is any acid that can be adopted in pickling in the prior art, such as organic acid and inorganic acid. Of these, hydrochloric acid, sulfuric acid or oxalic acid may be preferred. the

Wherein water washing can also refer to any water washing operation in the prior art, preferably clean water washes away impurities such as acid remaining on the flax fiber among the present invention, makes the pH value of flax fiber be about 7, keeps the cleanliness of flax fiber. the

The fiber beating is also any fiber beating process in the prior art. The impurity that has been detached from the flax fiber but still adheres to the surface of the flax fiber is removed by beating, usually 2 to 5 times of beating. Washing after blowing, the purpose is to wash away the residual oxidants and colloids on the flax fiber, keep the flax fiber clean again and keep the pH value of the flax fiber at about 7, dehydrate after washing, and use an industrial centrifugal dehydrator to wash the flax fiber After most of the moisture on the flax fiber is removed, it can be any washing operation of the prior art. the

The purpose of the oil supply is to prevent the colloid remaining on the surface of the flax fibers from bonding the flax fibers together after drying; the preparation and oil supply process of the oil agent: the oil agent is machine oil, and those skilled in the art generally know that the flax fiber What kind of mechanical oil should be used in the fiber oiling process, those skilled in the art do not need to do creative work on this, and the realization of the purpose of the present invention is not limited by the type of mechanical oil. However, it can be preferably spindle oil or white oil. Machine oil has a strong lubricating effect and can effectively prevent fibers from rebonding. The oil supply operation can refer to the existing ramie oil supply process. The preferred oil consumption of the present invention is: 10-40g of mechanical oil per kilogram of flax fiber, 1-8g of NaOH, 2-10g of detergent, and 8-12kg of water to stir and prepare Form an emulsified liquid, soak the flax fiber in it, and keep it warm for 0.5-3 hours under the environment of 60-100°C. the

The oiling can further preferably be 10-20g of mechanical oil per kilogram of flax fiber, 3-6g of NaOH, 2-8g of detergent, stirred with 10kg of water to prepare an emulsion, and the flax fiber is soaked in it and heated at 80°C. Keep warm for 1h in the environment. the

The deoiled water is to use an industrial centrifugal dehydrator to remove most of the moisture and slick oil on the oiled flax fiber, and then dry it. Those skilled in the art generally know the operation of this deoiled water, and no creative work is required. the

The softening is that the dried flax fibers are repeatedly kneaded by multiple pairs of rollers to make the fibers soft and loose, which is beneficial to subsequent processing. It can refer to the existing ramie softening operation. the

Because the moisture of the fiber after drying is too little, the fiber is rough and stiff, in order to increase the lubricity and softness of the surface of the flax fiber, and reduce the damage to the flax fiber in the subsequent processing such as mechanical opening, some oil and water should be added to the flax , namely the described step of humidifying the oil. the

Oil humidification can also refer to the existing linseed oil humidification operation, that is, those skilled in the art usually know the type of oil used in the oil humidification, and the purpose of the present invention is not limited by the type of oil. Yet for further improving flax fiber quality, the present invention is preferably: oil generally adopts vegetable oil, because it has certain viscosity, can suitably improve the cohesive force between the fibers. The amount of oil used: 5-40g of vegetable oil per kilogram of flax fiber, 1-10g of NaOH, 1-12g of detergent, and 50-200g of water (depending on the need for moisture regain) are stirred to make an emulsion, which is used in the softening process Evenly spray the emulsion on the flax fiber (the same as the existing ramie soft hemp operation). the

The oil humidification can also preferably use 10-20 g of vegetable oil per kilogram of flax fiber, 3-6 g of NaOH, 2-8 g of detergent, and 70-150 g of water. the

The stacking is to make the added oil and water permeate into the inside of the flax fiber evenly, it can be any stacking operation in the prior art, and the present invention preferably has a temperature of 20-60°C and a time of 15-60 hours; more Preferably, the temperature is 25-40° C. and the time is 24-48 hours. the

The mechanical opening is to feed the heaped flax fibers into the opening machine, so that the flax fibers are preliminarily loosened and decomposed, and then fed into the carding machine for careful opening and splitting. The specific operation can refer to any mechanical opening operation in the prior art. In order to further reduce the damage to the flax fiber during opening and carding in the present invention and ensure the fiber length, the preferred spacing between the licker-in roller and the cotton feeding plate is 0.10-7.50 mm, more preferably 0.12 to 5.50mm. the

In addition, the feeding plate of the carding machine can be further raised by 1-5 cm to increase the length of the carding process, preferably by 2-3 cm. This carding machine can be referred to the carding machine of prior art, and in the present invention, only cotton feeding plate is raised. That is to say, those skilled in the art know the structure of the carding machine with the cotton feeding plate, and those skilled in the art only need to make the cotton feeding plate too high by 1-5 cm. the

The refined flax fiber prepared by the present invention can utilize the existing spinning process equipment of wool spinning, ramie spinning and cotton spinning to complete the dry spinning process, and spin flax pure spinning or blended yarn with more than 60 public counts, which not only greatly shortens the The traditional linen wet-spinning process also overcomes the defect that wet-spun linen yarn can only be spun with coarse counts (mainly 24-36 public counts), and the yarn is stiff, which is difficult for knitting applications. The flax and its blended yarn processed by the method can be used as knitted fabrics, high-grade clothing and decorative fabrics, so that the flax fibers can be more widely used. the

Compared with prior art, advantage of the present invention is as follows:

1. The medicine mainly used in the chemical treatment process disclosed by the present invention is hydrogen peroxide, and the amount of alkali is less, which only plays an auxiliary role, so the pH value of the treated wastewater is 7-8, and the environmental pollution is greatly reduced;

2. The fine flax fiber prepared by the present invention greatly improves the spinnability (length and fineness, etc.) of the flax fiber, so that it can utilize existing cotton spinning or wool spinning equipment to complete dry spinning processing, and its cotton spinning process is: Blowroom→carding→pre-combing→combing→drawing→roving→spinning→post-processing; the process of wool spinning or ramie spinning is: carding→drawing→combing→pinning→roving→spinning→post-processing. Compared with the conventional flax wet spinning process, they greatly shorten the spinning process, and can spin pure flax or blended yarns of more than 60 public counts, overcoming the fact that traditional wet linen yarns can only be spun with coarse counts (mainly in 24-36 public count) yarn, and the yarn is stiff and difficult to be used in knitting, which meets the needs of spinning high-count yarn and making high-grade clothing and decorative fabrics. the

3. The flax fiber prepared by the present invention has high fineness and high strength, which further expands the field of use of the flax fiber. the

Detailed ways

The following examples will explain the present invention more specifically, but the present invention is not limited to these examples, nor are these examples limiting the present invention in any way. the

Example 1:

Beat flax into hemp and put it in the pickling pool, add 10 kg of water per kg of flax (bath ratio 1:10), add sulfuric acid to make the concentration of sulfuric acid 1g/L. Raise the temperature of the solution to 40°C, keep it warm for 40 minutes, take it out and wash the flax fiber with clean water, so that the pH value of the flax fiber reaches about 7; put the washed flax fiber into the oxidation solution, the bath ratio is 1:10, and oxidize The content of hydrogen peroxide (calculated as pure H ₂ O ₂ ) in the liquid is 3g/L, the content of sodium silicate is 3g/L, the content of potassium carbonate is 2g/L, the content of urea is 3g/L, and the content of JFC is 2g/L. Raise the temperature of the oxidizing solution from room temperature to 70°C at a constant speed, and control the heating time at 30 minutes. After reaching the temperature, let the oxidizing solution keep warm for 2 hours; beat the oxidized flax fiber twice with a wooden mallet; The flax fiber is cleaned to remove the medicines and impurities remaining on the surface of the fiber. Use a centrifugal dehydrator to dehydrate the flax fiber. After dehydration, in the emulsified oil soaked in the flax fiber, 10g of spindle oil, 3g of NaOH, and 2g of detergent per kilogram of flax fiber are stirred with 10kg of water to form an emulsion, and the flax fiber is soaked in it. Incubate at 80°C for 1 hour. The oiled fibers are dehydrated and dried by a dryer. The dried flax fibers are processed by a flax softening machine and sprayed with an emulsion. The ingredients are (per kilogram of flax): 10g of tea oil, 3g of NaOH, 2g of detergent, and 150g of water. 24h in a warehouse at 27°C. Use the opening machine with pin teeth to initially open the flax fiber after stacking, and then feed it into the carding machine for further opening and splitting. The carding machine raises the cotton board by 2cm, The gap between the licker-in roller and the cotton feeding board is 5.5mm.

The main performance indicators of the refined flax fiber prepared by the above process are as follows:

Table 1, the flax fiber main performance index that embodiment 1 prepares

the Fineness (Nm) Breaking Strength (cN/tex) Uneven Intensity (CV%) Elongation (%) Uneven elongation (CV%) Average length (mm) Flexibility Twist/dtex m linen 3500 8.0 21.31 3.66 10.3 40 1.21

Example 2:

Beat flax into hemp and put it in the pickling pool, add 10 kg of water per kg of flax (bath ratio 1:10), add sulfuric acid to make the concentration of sulfuric acid 2g/L. Raise the temperature of the solution to 50°C, keep it warm for 45 minutes, take it out and wash the flax fiber with clean water, so that the pH value of the flax fiber reaches about 7; put the washed flax fiber into the oxidation solution, the bath ratio is 1:10, The content of hydrogen peroxide (calculated as pure H ₂ O ₂ ) in the liquid is 4g/L, sodium silicate content 4g/L, sodium carbonate content 3g/L, urea content 4g/L, JFC content 2g/L. Raise the temperature of the oxidizing solution from normal temperature to 80°C at a constant speed, and control the heating time at 32 minutes. After the temperature reaches, let the oxidizing solution keep warm for 2.2 hours; beat the oxidized flax fiber with a wooden mallet twice; The flax fiber is cleaned to wash away the medicines and impurities remaining on the surface of the fiber. Use a centrifugal dehydrator to dehydrate the flax fiber. After dehydration, in the emulsified oil soaked in the flax fiber, use 12g of spindle oil, 4g of NaOH, and 3g of detergent per kilogram of flax fiber, stir with 10kg of water to form an emulsion, and soak the flax fiber in it. Incubate at 80°C for 1 hour. The oiled fibers are dehydrated and dried by a dryer. The dried flax fibers are processed by a flax softening machine and sprayed with an emulsion. The ingredients are (per kilogram of flax): 12g of rapeseed oil, 3.5g of NaOH, 8g of detergent, and 120g of water. 30h in a warehouse at a temperature of 25°C. Use the opening machine with pin teeth to initially open the flax fiber after stacking, and then feed it into the carding machine for further opening and splitting. The carding machine raises the cotton board by 2.5cm , The gap between the licker-in roller and the cotton feeding board is 0.12mm.

The main performance indicators of the refined flax fiber prepared by the above process are as follows:

The flax fiber main performance index prepared by table 2, embodiment 2

the Fineness (Nm) Breaking Strength (cN/tex) Uneven Intensity (CV%) Elongation (%) Uneven elongation (CV%) Average length (mm) Flexibility Twist/dtex m linen 3400 7.0 26.496 3.34 11.6 30 1.93

Example 3:

Beat flax into hemp and put it in the pickling pool, add 10 kg of water per kg of flax (bath ratio 1:10), add sulfuric acid to make the concentration of sulfuric acid 1.5g/L. Raise the temperature of the solution to 42°C, keep it warm for 50 minutes, take it out and wash the flax fiber with clean water, so that the pH value of the flax fiber reaches about 7; put the washed flax fiber into the oxidation solution, the bath ratio is 1:10, and oxidize The content of hydrogen peroxide (calculated as pure H ₂ O ₂ ) in the liquid is 5g/L, the content of sodium carbonate is 4g/L, the content of sodium silicate is 5g/L, the content of urea is 5g/L, and the content of JFC is 2g/L. Raise the temperature of the oxidizing solution from room temperature to 90°C at a constant speed, and control the heating time at 34 minutes. After reaching the temperature, let the oxidizing solution keep warm for 2.4 hours; beat the oxidized flax fibers with a wooden mallet for 5 times; The flax fiber is cleaned to wash away the medicines and impurities remaining on the surface of the fiber. Use a centrifugal dehydrator to dehydrate the flax fiber. After dehydration, in the emulsified oil soaked in the flax fiber, 15g of spindle oil, 5g of NaOH, and 4g of detergent are used for each kilogram of flax fiber, and stirred with 10kg of water to form an emulsion, and the flax fiber is soaked in it. Incubate at 80°C for 1 hour. The oiled fibers are dehydrated, then the oil and water are removed, and then dried by a dryer. The dried flax fiber is processed by a flax softening machine and sprayed with an emulsion. Its composition is (per kilogram of flax): 14g of rapeseed oil, 4g of NaOH, 7g of detergent, and 100g of water are stirred to form an emulsion, and then put into a temperature of 43 hours in the bin at 38°C; use the opening machine with needle teeth to preliminarily open the flax fibers after stacking, and then feed the opened fibers into the carding machine for further detailed opening, splitting, and carding. The feeding board of the cotton machine is raised by 3cm, and the distance between the licker-in roller and the feeding board is 4.4mm.

The main performance indicators of the refined flax fiber prepared by the above process are as follows:

Table 3, the flax fiber main performance index that embodiment 3 prepares

the Fineness (Nm) Breaking strength (cN/tex) Uneven Intensity (CV%) Elongation (%) Uneven elongation (CV%) Average length (mm) Flexibility Twist/dtex m linen 3300 6.5 24.342 3.31 12.3 50 1.87

Example 4:

Beat flax into hemp and put it in the pickling pool, add 10 kg of water per kg of flax (bath ratio 1:10), add sulfuric acid to make the concentration of sulfuric acid 1.2g/L. Raise the temperature of the solution to 45°C, keep it warm for 55 minutes, take it out and wash the flax fiber with clean water, so that the pH value of the flax fiber reaches about 7; put the washed flax fiber into the oxidation solution, the bath ratio is 1:10, and oxidize The content of hydrogen peroxide ( _calculated as pure _H2O2 ) in the liquid is 6g/L, the content of sodium silicate is 3.5g/L, the content of potassium carbonate is 2g/L, the content of urea is 3.5g/L, and the content of JFC is 2g/L. Raise the temperature of the oxidizing solution from normal temperature to 75°C at a constant speed, and control the heating time at 35 minutes. After the temperature reaches, let the oxidizing solution keep warm for 2.6 hours; beat the oxidized flax fibers with a wooden mallet for 5 times; The flax fiber is cleaned to wash away the medicines and impurities remaining on the surface of the fiber. Use a centrifugal dehydrator to dehydrate the flax fiber. After dehydration, soak the flax fiber in the emulsified oil. For each kilogram of flax fiber, use 17g of spindle oil, 3.5g of NaOH, and 5g of detergent. Stir with 10kg of water to form an emulsion, and impregnate the flax fiber in it. , kept at 80°C for 1h. The oiled fibers are dehydrated and dried by a dryer. The dried flax fiber is processed by a softening machine and sprayed with an emulsion. The composition is (per kilogram of flax): 16g of tea oil, 4.5g of NaOH, 6g of detergent, and 70g of water are stirred to form an emulsion, and then put Put it into a warehouse at a temperature of 35°C for 48 hours. Use the opening machine with needle teeth to initially open the flax fiber after stacking, and then feed it into the carding machine for further opening and splitting. The carding machine raises the cotton board by 2.2cm , The gap between the licker-in roller and the cotton feeding board is 3.5mm.

The main performance indicators of the refined flax fiber prepared by the above process are as follows:

The flax fiber main performance index prepared by table 4, embodiment 4

the Fineness (Nm) Breaking strength (cN/tex) Uneven Intensity (CV%) Elongation (%) Uneven elongation (CV%) Average length (mm) Flexibility Twist/dtex m linen 3200 5.0 27.534 2.34 13.6 35 2.23

Embodiment 5:

Beat the flax into hemp and put it in the pickling pool, add 10 kg of water per kg of flax (bath ratio 1:10), add hydrochloric acid, the concentration of hydrochloric acid is 1.8g/L. Raise the temperature of the solution to 48°C, keep it warm for 58 minutes, take it out and wash the flax fiber with clean water, so that the pH value of the flax fiber reaches about 7; put the washed flax fiber into the oxidation solution, the bath ratio is 1:10, and oxidize The content of hydrogen peroxide (calculated as pure H ₂ O ₂ ) in the liquid is 7g/L, the content of sodium silicate is 4.5g/L, the content of potassium carbonate is 3g/L, the content of urea is 4.5g/L, and the content of JFC is 2g/L. Raise the temperature of the oxidizing solution from normal temperature to 85°C at a constant speed, and control the heating time at 37 minutes. After the temperature reaches, let the oxidizing solution keep warm for 2.8 hours; beat the oxidized flax fiber with a wooden mallet for 5 times; The flax fiber is cleaned to wash away the medicines and impurities remaining on the surface of the fiber. Use a centrifugal dehydrator to dehydrate the flax fiber. After dehydration, soak the flax fiber in the emulsified oil. For each kilogram of flax fiber, use 19g of spindle oil, 4.5g of NaOH, and 6g of detergent. Stir with 10kg of water to form an emulsion, and soak the flax fiber in it , kept at 80°C for 1h. The oiled fibers are dehydrated and dried by a dryer. The flax fibers after drying are processed by a flax softening machine and sprayed with an emulsion. The composition is (per kilogram of flax): 18g of rapeseed oil, 5g of NaOH, 5g of detergent, and 80g of water are stirred to form an emulsion, and then put into the emulsion at a temperature of 38h in a warehouse at 40°C. Use the opening machine with pin teeth to initially open the flax fiber after stacking, and then feed it into the carding machine for further opening and splitting. The carding machine raises the cotton board by 2.7cm , The gap between the licker-in roller and the cotton feeding board is 2.7mm.

The main performance indicators of the refined flax fiber prepared by the above process are as follows:

Table 5, main performance index of the flax fiber prepared by embodiment 5

the Fineness (Nm) Breaking Strength (cN/tex) Uneven Intensity (CV%) Elongation (%) Uneven elongation (CV%) Average length (mm) Flexibility Twist/dtex m linen 3000 5.5 27.534 2.34 13.6 40 2.23

Embodiment 6:

Beat the flax into hemp and put it in the pickling pool, add 10 kg of water per kg of flax (bath ratio 1:10), add hydrochloric acid, the concentration of hydrochloric acid is 2.1g/L. Raise the temperature of the solution to 38°C, keep it warm for 60 minutes, take it out and wash the flax fiber with clean water, so that the pH value of the flax fiber reaches about 7; put the washed flax fiber into the oxidation solution, the bath ratio is 1:10, and oxidize The content of hydrogen peroxide ( _calculated as pure _H2O2 ) in the solution is 8g/L, the content of sodium silicate is 5.0g/L, the content of potassium carbonate is 4g/L, the content of urea is 5.0g/L, and the content of JFC is 2g/L. Raise the temperature of the oxidizing solution from normal temperature to 90°C at a constant speed, and control the heating time at 40 minutes. After reaching the temperature, let the oxidizing solution keep warm for 3 hours; beat the oxidized flax fiber with a wooden mallet for 5 times; The flax fiber is cleaned to remove the medicines and impurities remaining on the surface of the fiber. Use a centrifugal dehydrator to dehydrate the flax fiber. After dehydration, in the emulsified oil soaked in the flax fiber, use 20g of spindle oil, 6g of NaOH, and 8g of detergent per kilogram of flax fiber, stir with 10kg of water to form an emulsion, and soak the flax fiber in it. Incubate at 80°C for 1 hour. The oiled fibers are dehydrated and dried by a dryer. The dried flax fibers are processed by a flax softening machine and sprayed with an emulsion. The ingredients are (per kilogram of flax): 20g of tea oil, 6g of NaOH, 4g of detergent, and 90g of water are stirred to form an emulsion, and then placed in a temperature 34h in a warehouse at 33°C. Use the opening machine with pin teeth to initially open the flax fiber after stacking, and then feed it into the carding machine for further opening and splitting. The carding machine raises the cotton board by 2.9cm , The gap between the licker-in roller and the cotton feeding board is 1.5mm.

The main performance indicators of the refined flax fiber prepared by the above process are as follows:

Table 6, the flax fiber main performance index that embodiment 6 prepares

the Fineness (Nm) Breaking Strength (cN/tex) Uneven Intensity (CV%) Elongation (%) Uneven elongation (CV%) Average length (mm) Flexibility Twist/dtex m linen 2800 6.0 27.534 2.34 13.6 70 2.23

Embodiment 7:

Beat the flax into hemp and put it in the pickling pool, add 8 kg of water per kg of flax (bath ratio 1:8), add sulfuric acid, the concentration of sulfuric acid is 2.3g/L. Raise the temperature of the solution to 35°C, keep it warm for 30 minutes, take it out and wash the flax fiber with clean water, so that the pH value of the flax fiber reaches about 7; put the washed flax fiber into the oxidation solution, the bath ratio is 1:8, and oxidize The content of hydrogen peroxide ( _calculated as pure _H2O2 ) in the liquid is 9g/L, the content of sodium silicate is 2g/L, the content of sodium carbonate is 5g/L, the content of urea is 6g/L, and the content of JFC is 1g/L. Raise the temperature of the oxidizing solution from room temperature to 93°C at a constant speed, and control the heating time at 20 minutes. After reaching the temperature, let the oxidizing solution keep warm for 3.2 hours; beat the oxidized flax fibers with a wooden mallet for 5 times; The flax fiber is cleaned to wash away the medicines and impurities remaining on the surface of the fiber. Use a centrifugal dehydrator to dehydrate the flax fiber. After dehydration, in the emulsified oil soaked in the flax fiber, use 23g of white oil, 1g of NaOH, and 9g of detergent per kilogram of flax fiber, stir with 8kg of water to form an emulsion, and soak the flax fiber in it. Incubate at 60°C for 3 hours. The oiled fibers are dehydrated and dried by a dryer. The dried flax fiber is processed by a flax softening machine and sprayed with an emulsion. Its composition is (per kilogram of flax): 5g of vegetable oil, 1g of NaOH, 1g of detergent, and 50g of water are stirred to form an emulsion, and then put into the emulsion at a temperature of 60h in a warehouse at 20°C. Use the opening machine with pin teeth to initially open the flax fiber after stacking, and then feed it into the carding machine for further opening and splitting. The carding machine raises the cotton board by 1.0cm , The gap between the licker-in roller and the cotton feeding board is 7.0mm.

The main performance indicators of the refined flax fiber prepared by the above process are as follows:

Table 7, main performance index of flax fiber prepared by embodiment 7

the Fineness (Nm) Breaking Strength (cN/tex) Uneven Intensity (CV%) Elongation (%) Uneven elongation (CV%) Average length (mm) Flexibility Twist/dtex m linen 2600 4.5 27.534 2.34 13.6 90 2.23

Embodiment 8:

Beat the flax into hemp and put it in the pickling pool, add 9 kg of water per kg of flax (bath ratio 1:9), add oxalic acid, the concentration of oxalic acid is 2.4g/L. Raise the temperature of the solution to 70°C, keep it warm for 70 minutes, take it out and wash the flax fiber with clean water, so that the pH value of the flax fiber reaches about 7; put the washed flax fiber into the oxidation solution, the bath ratio is 1:9, and oxidize The content of hydrogen peroxide (calculated as pure H ₂ O ₂ ) in the liquid is 10g/L, sodium silicate content 6g/L, sodium carbonate content 6g/L, urea content 7g/L, JFC content 3g/L. Raise the temperature of the oxidizing solution from room temperature to 95°C at a constant speed, and control the heating time at 45 minutes. After reaching the temperature, let the oxidizing solution keep warm for 3.5 hours; beat the oxidized flax fibers with a mallet for 5 times; The flax fiber is cleaned to wash away the medicines and impurities remaining on the surface of the fiber. Use a centrifugal dehydrator to dehydrate the flax fiber. After dehydration, in the emulsified oil soaked in the flax fiber, use 27g of white oil, 2g of NaOH, and 9.5g of detergent per kilogram of flax fiber, stir with 9kg of water to form an emulsion, and impregnate the flax fiber in it. Incubate at 70°C for 2 hours. The oiled fibers are dehydrated and dried by a dryer. The dried flax fiber is processed through a flax softening machine and sprayed with an emulsion. Its composition is (per kilogram of flax): 8g of vegetable oil, 2g of NaOH, 9g of detergent, and 200g of water are stirred to form an emulsion, and then put into a temperature of 52h in a warehouse at 60°C. Use the opening machine with pin teeth to initially open the flax fiber after stacking, and then feed it into the carding machine for further opening and splitting. The carding machine raises the cotton board by 5.0cm , The gap between the licker-in roller and the cotton feeding board is 7.5mm.

The main performance indicators of the refined flax fiber prepared by the above process are as follows:

Table 8, main performance index of flax fiber prepared by embodiment 8

the Fineness (Nm) Breaking Strength (cN/tex) Uneven Intensity (CV%) Elongation (%) Uneven elongation (CV%) Average length (mm) Flexibility Twist/dtex m linen 2300 4.0 27.534 2.34 13.6 85 2.23

Embodiment 9:

Beat the flax into hemp and put it in the pickling pool, add 11 kg of water per kg of flax (bath ratio 1:11), add sulfuric acid, the concentration of sulfuric acid is 3.0g/L. Raise the temperature of the solution to 60°C, keep it warm for 50 minutes, take it out and wash the flax fiber with clean water, so that the pH value of the flax fiber reaches about 7; put the washed flax fiber into the oxidation solution, the bath ratio is 1:11, The content of hydrogen peroxide ( _calculated as pure _H2O2 ) in the solution is 11g/L, sodium silicate content is 7g/L, potassium carbonate content is 5g/L, urea content is 8g/L, and JFC content is 4g/L. Raise the temperature of the oxidizing solution from room temperature to 97°C at a constant speed, and control the heating time at 50 minutes. After the temperature reaches, let the oxidizing solution keep warm for 3.8 hours; beat the oxidized flax fibers with a wooden mallet for 5 times; The flax fiber is cleaned to wash away the medicines and impurities remaining on the surface of the fiber. Use a centrifugal dehydrator to dehydrate the flax fiber. After dehydration, in the emulsified oil soaked in the flax fiber, use 35g of white oil, 7g of NaOH, and 9.0g of detergent per kilogram of flax fiber, stir with 11kg of water to form an emulsion, and impregnate the flax fiber in it. Incubate at 90°C for 2.5 hours. The oiled fibers are dehydrated and dried by a dryer. The flax fibers after drying are processed by a softening machine and sprayed with an emulsion. The composition is (per kilogram of flax): 30g of vegetable oil, 7g of NaOH, 11g of detergent, and 180g of water are stirred to form an emulsion, and then put into the emulsion at a temperature of 15h in a warehouse at 55°C. Use the opening machine with pin teeth to initially open the flax fiber after stacking, and then feed it into the carding machine for further opening and splitting. The carding machine raises the cotton board by 4.0cm , The gap between the licker-in roller and the cotton feeding board is 6.5mm.

The main performance indicators of the refined flax fiber prepared by the above process are as follows:

Table 9, main performance index of flax fiber prepared by embodiment 9

the Fineness (Nm) Breaking strength (cN/tex) Uneven Intensity (CV%) Elongation (%) Uneven elongation (CV%) Average length (mm) Flexibility Twist/dtex m linen 2000 3.5 27.534 2.34 13.6 90 2.23

Embodiment 10:

Beat the flax into hemp and put it in the pickling pool, add 12 kg of water per kg of flax (bath ratio 1:12), add oxalic acid, the concentration of oxalic acid is 2.8g/L. Raise the temperature of the solution to 65°C, take it out after 80 minutes of heat preservation, and wash the flax fiber with clean water, so that the pH value of the flax fiber reaches about 7; put the washed flax fiber into the oxidation solution, the bath ratio is 1:12, and oxidize The content of hydrogen peroxide (calculated as pure H ₂ O ₂ ) in the liquid is 12g/L, sodium silicate content 8g/L, potassium carbonate content 6g/L, urea content 6.5g/L, JFC content 4g/L. Raise the temperature of the oxidizing solution from room temperature to 100°C at a constant speed, and control the heating time at 60 minutes. After the temperature reaches, let the oxidizing solution keep warm for 4.0 hours; beat the oxidized flax fibers with a wooden mallet for 5 times; The flax fiber is cleaned to wash away the medicines and impurities remaining on the surface of the fiber. Use a centrifugal dehydrator to dehydrate the flax fiber. After dehydration, in the emulsified oil soaked in the flax fiber, use 40g of white oil, 8g of NaOH, and 10.0g of detergent per kilogram of flax fiber, stir with 12kg of water to form an emulsion, and soak the flax fiber in it. Incubate at 100°C for 0.5h. The oiled fibers are dehydrated and dried by a dryer. The flax fibers after drying are processed by a flax softening machine and sprayed with an emulsion. The ingredients are (per kilogram of flax): 40g of vegetable oil, 10g of NaOH, 12g of detergent, and 60g of water are stirred to form an emulsion, and then placed in a temperature of 20h in a warehouse at 50°C. Use the opening machine with pin teeth to initially open the flax fiber after stacking, and then feed it into the carding machine for further opening and splitting. The carding machine raises the cotton board by 4.5cm , The gap between the licker-in roller and the cotton feeding board is 0.1mm.

The main performance indicators of the refined flax fiber prepared by the above process are as follows:

Table 10, main performance index of flax fiber prepared by embodiment 10

the Fineness (Nm) Breaking Strength (cN/tex) Uneven Intensity (CV%) Elongation (%) Uneven elongation (CV%) Average length (mm) Flexibility Twist/dtex m linen 1500 3.0 27.534 2.34 13.6 70 2.23

Spinning the refined flax fiber. the

Example 11

The prepared flax fiber is spun into high-count flax fiber pure spinning and blended yarn through the following spinning process:

Pure spinning: cleaning→carding→(pre-combing→combing)→drawing→roving→spinning→post-processing. the

→Drawing 2→Roving→Spinning→Post-processing. the

Note: In the above process, the pre-merging → combing process is used when spinning high-count yarns (pure spinning above 50 public counts, blended spinning above 60 public counts); when spinning hemp/cotton yarns below 60 public counts, the cotton may not be combed; Chemical fibers are not combed. the

The main quality indicators of refined flax fiber pure spinning are as follows:

Table 11, main performance index of flax pure spinning prepared by embodiment 11

the Linear Density (Nm) Strength (cN/tex) Elongation (%) Evenness CV(%) Kilometer Details (-30%) Kilometer Thickness (+50%) Kilometer Grain (+200%) linen yarn 60 13.14 2.45 23.4 1335 1218 780

The main quality indicators of refined flax fiber blended yarn are as follows:

Table 12, the main performance indicators of the flax blended yarn prepared in Example 11

the Linear Density (Nm) Strength (cN/tex) Elongation (%) Evenness CV(%) Kilometer Details (-30%) Kilometer Thickness (+50%) Kilometer Grain (+200%) Linen 55/Cotton 45 120 16.2 3.05 24.6 1019 2259 2622 Linen 70/Viscose 30 67 7.92 1.76 22.7 715 935 455

Example 12

The prepared flax fiber is spun into flax/ramie blended yarn through the ramie spinning process:

Table 13, the main performance indicators of the 36 public count flax 50/ramie 50 pure blended yarns prepared in Example 12

the Linear Density (Nm) Strength (cN/tex) Elongation (%) Evenness CV(%) Kilometer Details (-30%) Kilometer Thickness (+50%) Kilometer Grain (+200%) Linen 50/ramie 50 36 18.5 3.32 25.2 537 860 1180

The present invention also provides some comparative examples, to illustrate that the preparation method of the present invention has advantages:

Comparative example 1

Table 14. Main performance indicators of flax fibers prepared by different methods

the Fineness (Nm) Breaking strength (cN/tex) Uneven Intensity (CV%) Elongation (%) Uneven elongation (CV%) Flexibility Twist/dtex m 1 900 14.53 30.953 2.56 25.2 1.24 2 1463 4.75 28.341 2.78 15.5 1.53 3 1253 4.42 28.712 2.13 16.8 1.42 4 3200 5.0 27.534 2.34 13.6 2.23

Wherein 1 is prepared according to the method of Example 1 of patent application 88102614;

Wherein 2 is prepared according to the method of Example 1 of patent application 200610031004;

Wherein 3 is prepared according to the method of embodiment 2 of patent application 200610031004;

Wherein 4 is prepared according to the method of Example 4 of the present invention. the

Comparative example 2

This comparative example illustrates the influence of different oxidation parameters on product quality. This comparative example is according to the method of Example 1, and specific parameters are adjusted. When examining one parameter, the other parameters are held constant. For example, when investigating the influence of sodium carbonate consumption, other parameters such as sodium silicate, urea etc. all adopt a certain fixed value in the scheme of the present invention that has been determined. the

Table 15. Effect of different oxidation parameters on flax fiber fineness (Nm)

Dosage 1g 2g 3g 4g 6g 8g 9g Sodium carbonate 2207 2603 2750 3207 1672 1426 1390 Sodium silicate 1750 1975 2522 3512 1942 1523 1245 Urea 1560 1753 2492 3218 1795 1428 1415 JFC 1618 2482 1852 1756 1472 1428 1430

The above data shows that when the preparation method of the present invention is adopted, flax fibers with high fineness can be prepared, and the flax fibers obtained by the preferred scheme have higher fineness. the

Table 16. Effect of different oxidation parameters on the breaking strength of flax fibers (cN/tex) 

Dosage 1g 2g 3g 4g 6g 8g 9g Sodium carbonate 4.72 4.85 4.95 4.89 4.76 4.54 3.95 Sodium silicate 4.71 4.87 4.92 4.82 4.72 4.73 4.51 Urea 4.52 4.84 4.93 4.87 4.75 4.70 4.23 JFC 4.68 4.89 4.82 4.78 4.52 4.28 3.75

The above data shows that when the preparation method of the present invention is adopted, high-strength flax fibers can be prepared, and the flax fibers obtained by the preferred scheme have higher strength. the

In addition, the ranges of the various parameters of the technical solution of the present invention are combined and tested one by one. No matter how the parameters are combined, the obtained fiber strength and fineness can conform to the above-mentioned rules, that is, the technical solution of the present invention. No matter how the parameter ranges are combined, the properties of the obtained flax fibers are better than the parameters outside the range, and the properties of the flax fibers obtained in the preferred parameter ranges can be further improved. Due to limited space, the present invention will not list the experimental data of other combinations one by one. the

Claims (44)

1. A flax fiber, characterized in that the flax fiber strength is 3.0 to 8.0cN/dtex, and the fineness is 1500 to 3500 public branches; the preparation method of the flax fiber comprises pickling, washing, oxidation, and fiberizing , oiling, deoiling water, soft hemp, oiling and humidification, stacking and mechanical opening steps, the oxidation step is to use 8-12 kg of water per kilogram of flax fiber, and first add sodium carbonate or potassium carbonate, silicic acid to the water Sodium, urea and osmotic agent JFC, the addition amount is 2~6g of sodium carbonate or potassium carbonate, 2~8g of sodium silicate, 2~8g of urea and 1~4g of osmotic agent JFC per liter of water after adding, add _H2O after complete dissolution _2. The amount of H ₂ O ₂ added is calculated as pure H ₂ O ₂ , which is 3-12g of H ₂ O ₂ per liter of water after addition. 2. The flax fiber according to claim 1, characterized in that the strength of the flax fiber is 4.0-7.0 cN/dtex, and the fineness is 1500-3000 metric. 3. The flax fiber according to claim 2, characterized in that the strength of the flax fiber is 4.5-6.5 cN/dtex, and the fineness is 1800-2800 metric. 4. The flax fiber according to claim 3, characterized in that the strength of the flax fiber is 5.0-6.0 cN/dtex, and the fineness is 2300-2700 metric. 5. The flax fiber according to claim 1, characterized in that the length of the flax fiber is 20-100 mm. 6. The flax fiber according to claim 5, characterized in that the length of the flax fiber is 30-80 mm. 7. The flax fiber according to claim 6, characterized in that the length of the flax fiber is 40-60 mm. 8. The flax fiber according to claim 1, characterized in that, every kilogram of flax fiber uses 10kg of water, and every liter of water contains 2-4g of sodium carbonate or potassium carbonate, 3-5g of sodium silicate, 3-5g of urea, and 2g of penetrant JFC , The amount of H ₂ O ₂ added is calculated as pure H ₂ O ₂ , which is 3-8g of H ₂ O ₂ per liter of water after addition. 9. The flax fiber according to claim 1, characterized in that, the oxidizing step is to put the flax in the oxidizing solution, raise the temperature from room temperature to 70-100°C at a constant speed, control the heating time at 20-60min, and the oxidation reaction time 2.0 to 4.0 hours. 10. The flax fiber according to claim 9, characterized in that the oxidation step is to raise the temperature from room temperature to 70-90°C at a constant speed, the heating time is controlled at 30-40 minutes, and the oxidation reaction time is 2.0-3.0 hours. 11. The flax fiber according to claim 1, characterized in that the acid concentration in the pickling step is 1 to 3 g/L, the temperature is 35 to 70° C., and the bath ratio is 1:8 to 1:12, Pickling time is 30-80 minutes. 12. The flax fiber according to claim 11, characterized in that, the acid concentration in the pickling step is 1 to 2 g/L, the temperature is 40 to 50° C., the bath ratio is 1:10, and the pickling time is 40～60min. 13. The flax fiber according to claim 1, characterized in that, in the oiling step, the oil agent is mechanical oil; 10-40 g of mechanical oil, 1-8 g of NaOH, and 2-10 g of detergent are used per kilogram of flax fiber , stirred with 8-12kg of water to prepare an emulsion, impregnated the flax fiber in it, and kept it warm for 0.5-3 hours in an environment of 60-100°C. 14. The flax fiber according to claim 13, characterized in that, the oiling agent in the described oiling step is spindle oil or white oil. 15. The flax fiber according to claim 14, characterized in that, the oil agent in the described oiling step is spindle oil. 16. The flax fiber according to claim 13, characterized in that, 10-20g of machine oil per kilogram of flax fiber, 3-6g of NaOH, and 2-8g of detergent are mixed with 10kg of water to form an emulsion, and the flax The fibers are immersed in it, and kept at 80° C. for 1 hour. 17. The flax fiber according to claim 1, characterized in that vegetable oil is used in the step of oiling and humidifying; vegetable oil, NaOH, detergent and water are stirred to form an emulsion, which is evenly Spray the emulsified liquid on the exported flax fiber; use 5-40g of vegetable oil, 1-10g of NaOH, 1-12g of detergent and 50-200g of water per kilogram of flax fiber. 18. The flax fiber according to claim 17, characterized in that tea oil or rapeseed oil is used in the described oiling and humidifying step. 19. The flax fiber according to claim 17, characterized in that 10-20 g of vegetable oil, 3-6 g of NaOH, 2-8 g of detergent, and 70-150 g of water are used per kilogram of flax fiber. 20. The flax fiber according to claim 1, characterized in that, the storage bin is at a temperature of 20-60°C and a time of 15-60 hours. 21. The flax fiber according to claim 20, characterized in that, the temperature of the storage bin is 25-40° C. and the time is 24-48 hours. 22. The flax fiber according to claim 1, characterized in that, in the mechanical opening step, the distance between the licker-in roller and the feeding plate is 0.10-7.50 mm. 23. The flax fiber according to claim 22, characterized in that the distance between the licker-in roller and the feeding plate is 0.12-5.50 mm. 24. The flax fiber according to claim 22 or 23, characterized in that, in the mechanical opening step, the feeding plate of the carding machine is 1-5 cm higher than the machine frame. 25. The flax fiber according to claim 24, characterized in that, in the mechanical opening step, the cotton feeding plate of the carding machine is 2-3 cm higher than the machine frame. 26. The preparation method of the flax fiber described in any one of claims 1 to 25, comprising the steps of pickling, washing, oxidation, fiber beating, oiling, deoiling water, softening, oiling and humidification, stacking and mechanical opening , it is characterized in that, described oxidation step is, every kilogram of flax fiber uses 8～12kg of water, firstly adds sodium carbonate or potassium carbonate, sodium silicate, urea and penetrant JFC in water, and the addition amount is after adding, every liter of water contains carbonic acid Sodium or potassium carbonate 2~6g, sodium silicate 2~8g, urea 2~8g and penetrant JFC 1~4g, add H ₂ O ₂ after completely dissolved, the amount of H ₂ O ₂ added is calculated as pure H ₂ O ₂ After that, each liter of water contains 3~12g of H ₂ O ₂ . 27. The preparation method according to claim 26, characterized in that 10 kg of water per kilogram of flax fiber, 2-4 g of sodium carbonate or potassium carbonate, 3-5 g of sodium silicate, 3-5 g of urea, and 2 g of penetrant JFC per liter of water , The amount of H ₂ O ₂ added is calculated as pure H ₂ O ₂ , which is 3-8g of H ₂ O ₂ per liter of water after addition. 28. The preparation method according to claim 26, characterized in that, the oxidation step is to put the flax into the oxidizing solution and raise the temperature from room temperature to 70-100°C at a constant speed, the heating time is controlled at 20-60min, and the oxidation reaction time 2.0 to 4.0 hours. 29. The preparation method according to claim 28, characterized in that, the oxidation step is to put the flax in the oxidation solution, raise the temperature from room temperature to 70-90°C at a constant speed, control the heating time at 30-40min, and the oxidation reaction time 2.0 to 3.0 hours. 30. The preparation method according to claim 26, characterized in that the concentration of acid in the pickling step is 1-3g/L, the temperature is 35-70°C, and the bath ratio is 1:8-1:12, Pickling time is 30-80 minutes. 31. The preparation method according to claim 30, characterized in that the acid concentration in the pickling step is 1-2 g/L, the temperature is 40-50°C, the bath ratio is 1:10, and the pickling time is 40～60min. 32. The preparation method according to claim 26, characterized in that, in the oil supply step, the oil agent is machine oil; 10-40 g of machine oil, 1-8 g of NaOH, and 2-10 g of detergent are used per kilogram of flax fiber , stirred with 8-12kg of water to prepare an emulsion, impregnated the flax fiber in it, and kept it warm for 0.5-3 hours in an environment of 60-100°C. 33. The preparation method according to claim 32, characterized in that the oil agent in the oil supply step is spindle oil or white oil. 34. The preparation method according to claim 33, characterized in that, the oil agent in the described oiling step is spindle oil. 35. The preparation method according to claim 32, characterized in that 10-20 g of machine oil, 3-6 g of NaOH, and 2-8 g of detergent are used for every kilogram of flax fiber, stirred with 10 kg of water to prepare an emulsion, and the flax The fibers are immersed in it, and kept at 80° C. for 1 hour. 36. The preparation method according to claim 26, characterized in that vegetable oil is used in the oiling and humidifying step; vegetable oil, NaOH, detergent and water are stirred to form an emulsion, which is evenly distributed at the output end of the softening machine Spray the emulsified liquid on the exported flax fiber; use 5-40g of vegetable oil, 1-10g of NaOH, 1-12g of detergent and 50-200g of water per kilogram of flax fiber. 37. The preparation method according to claim 36, characterized in that tea oil or rapeseed oil is used in the step of humidifying the oil. 38. The preparation method according to claim 36, characterized in that 10-20 g of vegetable oil, 3-6 g of NaOH, 2-8 g of detergent and 70-150 g of water are used per kilogram of flax fiber. 39. The preparation method according to claim 26, characterized in that, the temperature of the storage bin is 20-60°C, and the time is 15-60 hours. 40. The preparation method according to claim 39, characterized in that, the temperature of the storage bin is 25-40° C., and the time is 24-48 hours. 41. The preparation method according to claim 26, characterized in that, in the mechanical opening step, the distance between the licker-in roller and the cotton feeding plate is 0.10-7.50 mm. 42. The preparation method according to claim 41, characterized in that, in the mechanical opening step, the distance between the licker-in roller and the cotton feeding plate is 0.12-5.50 mm. 43. The preparation method according to claim 41 or 42, characterized in that, in the mechanical opening step, the cotton feeding plate of the carding machine is 1-5 cm higher than the machine frame. 44. The preparation method according to claim 43, characterized in that, in the mechanical opening step, the feeding plate of the carding machine is raised 2-3 cm higher than the machine frame.